Patent GB-425178-A (GB)
Title: Improvements in and relating to milking machines
IPC: A01J5/04
Filed: 1933-09-15
Abstract: 425,178. Cow-milkers. PETHERAM, G. F., St. Aubyn Street, New Plymouth, New Zealand. Sept. 15, 1933, Nos. 25622 and 25623.. Convention dates, Sept. 15, 1932 and Jan. 6, 1933. [Class 84] [See also Groups XXVI and XXVIII] A milking-machine comprises a suction pump 1, Fig. 1, a pulsator 18 consisting of a casing divided into two compartments 20, 21, Fig. 10, one 20 being connected with the teat cup inflations and the other 21 with the pump 1, spring pressed disc valves 31, 32 being provided in compartment 21 for cutting it off from compartment 20 and from the atmosphere respectively, a rod 14 extending into the pulsator casing operating the valves 31, 32 preferably through collars 33 pinned on the rod which is reciprocated by a cam 11 driven by the pump 1. In the construction described, vacuum is produced by the pump 1, which is driven from a motor 3 through a belt 2, the speed of the pump being regulated by using belt pulleys of suitable diameter. The pulsator 18 is actuated from the shaft 5 of the pump 1 through a worm drive 6, 7 which rotates a spindle 8 carrying at one end cam 11 which actuates the rod 14. The cam 11 is shaped to give a 60 /40 period for the squeeze and release action respectively of the teat cups. The chamber 20 of the pulsator 18 has an outlet 38 leading to the pump 1 and chamber 21 has an outlet 37 leading to the lower chamber 40, Fig. 1, of a releaser and thence to the air line 48 for operating the teat cups. The chamber 21 has a screw-in cover 26 provided with air passages 29 adapted to be closed by a valve 32 on spindle 14 when the connection between chambers 20, 21 is open, and to be opened when this connection is closed, thus connecting the chamber 21 alternately to vacuum and the atmosphere to operate the inflations in the teat cups. Springs 34, 35 and rubber rings 27, 30 ensure positive and air-tight closure of the valves 31, 32. The releaser consists of upper and lower chambers 44, 40, Fig. 3, which are detachably secured together, a flap valve 56 being placed at the joint, a similar valve 67 closing the discharge opening 60 of chamber 40. The chamber 44 has an inlet pipe 47 connected to the milk line and has a lid 43 with aT-piece 42 connected to the pump 1 by which a vacuum is instantly maintained in the chamber. Chamber 40 has nipples 39, 45 to which are secured flexible connections to the air line to the teat cups and to the pulsator 18 respectively. The milk line consists of lengths of glass or nickel-plated tubing 49, Fig. 2, connected by unions 76 the end flanges 77 of which are countersunk to take rubber jointing rings 78, which are drawn inwards by the vacuum in the line b from a seal. At intervals, unions 83 are provided, having a tube 85 connected by rubber tubing 86 to the glass or nickelplated tubing 105 leading to the teat cups, and having a screwed cap 87 which can be removed for cleaning The end fitting 88 has an extension 89 to which the vacuum gauge is secured and has a release valve consisting of a ball 92, Fig. 19, held by a spring 93 against the edges of a hole 95 in a member 91 screwed on an extension 90 of the fitting. The release valve may be adjusted to control the degree of vacuum used by screwing in or out the member 91. The milk line is detachably secured to a supporting board 82 by means of hooks 79 on fittings 76, 83, which engage brackets 81 attached to the board 82. The air line is also constructed of lengths of glass or nickel-plated tubing 48 which are connected to extensions 98 on unions 96 by rubber tubing 99. At intervals, unions 97 are provided having extensions 103 which are connected through rubber tubing 104 and glass or nickel plated tubing 106 to the teat cups. The unions 96, 97 have hooks 100 engaging brackets 102 on the board 82. In operation, the milk is drawn into chamber 44 of the releaser which is under constant vacuum. The lower chamber 44 is alternately under vacuum and atmospheric pressure and the milk during the vacuum phase flows past valve 56 to chamber 44, and during the other phase is released past valve 60. Cleansing liquid may be drawn from the teat cups through the air and milk lines and out through the releaser without dismantling these lines.